Our efforts to develop a physical map of chromosome 3 have resulted in well localized YACs and YAC contigs for approximately 70% of the chromosome, as well as an extensive collection of molecular probes and somatic cell hybrids. These studies provide a powerful foundation for subsequent efforts aimed at improving the fidelity and detail of the physical map, steps essential for achieving the goals of the Genome Project. We propose to build on this foundation by converting the present coarse physical map into one which is highly detailed, integrated, extremely useful and ready for DNA sequence analysis. We propose to complete development of the YAC contig, construct additional contigs from smaller clones of higher fidelity, develop STS markers every 100 kb and a transcriptional map for select chromosome 3 segments, as well as to interface our chromosome 3 database with other systems (such as IGD) in order to improve accessibility and distribution of results. In this proposal, robotics and automation are essential components of the experimental design. This proposal addresses several goals of the Genome Project including the development of a highly detailed physical map for chromosome 3 using clones with improved stability and lowered chimerism, developing of a high density STS map, improvement in gene isolation techniques coupled with generation of a transcriptional map for several multi-megabase regions and continued development of software for storing and searching through mapping information.